238 research outputs found

    Enhanced propagation of motile bacteria on surfaces due to forward scattering

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    How motile bacteria move near a surface is a problem of fundamental biophysical interest and is key to the emergence of several phenomena of biological, ecological and medical relevance, including biofilm formation. Solid boundaries can strongly influence a cell's propulsion mechanism, thus leading many flagellated bacteria to describe long circular trajectories stably entrapped by the surface. Experimental studies on near-surface bacterial motility have, however, neglected the fact that real environments have typical microstructures varying on the scale of the cells' motion. Here, we show that micro-obstacles influence the propagation of peritrichously flagellated bacteria on a flat surface in a non-monotonic way. Instead of hindering it, an optimal, relatively low obstacle density can significantly enhance cells' propagation on surfaces due to individual forward-scattering events. This finding provides insight on the emerging dynamics of chiral active matter in complex environments and inspires possible routes to control microbial ecology in natural habitats

    Buerger's Disease (Thromboangiitis Obliterans): a Diagnostic Challenge

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    Buerger's disease or Thromboangiitis obliterans is a segmental inflammatory disease that affects the vessels and nerves of the extremities. It usually affects men below 45 years old and correlates with tobacco, as a predisposing factor. The authors present the case of a 34-year-old male, with ulcers in the fingertips with progressive worsening: acrocyanosis, slow healing, necrosis and finally loss of substance. Dorsalis pedis and posterior tibial pulses were not palpable. Personal history of heavy smoking was (20 pack-years). The angiography revealed proximal occlusion of the left posterior tibial and interosseal arteries, with distal circulation by the anterior tibial artery. He was submitted to disarticulation of the second left toe and therapy with pentoxifyline and iloprost infusion, calcium antagonist, antiplatelet drugs, statin and low molecular weight heparin (later replaced by oral anticoagulation). Improvement was seen of active vascular lesions and pain symptoms.info:eu-repo/semantics/publishedVersio

    Actinobacillus Endocarditis Associated with Hypertrophic Cardiomyopathy

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    Infective endocarditis can be associated with complex clinical presentations, sometimes with a difficult multi-disciplinary management. Actinobacillus actinomycetemcomitans belongs to the Haemophilus species, Actinomycetemcomitans, Cardiobacterium hominis, Eikenella corrodens and Kingella species group, responsible for 5% to 10% of infective endocarditis in native heart valves. These organisms have slow fastidious growth pattern, often associated with negative cultures, and cause systemic embolism with abscess formation. The authors present the case of a 59-year-old man, admitted due to fever of unknown origin, with a personal history of obstructive hypertrophic cardiomyopathy and recent dental manipulation. The diagnosis of mitral valve's endocarditis was established after a transoesophageal ecocardiography, with a late isolation of A actinomycetemcomitans in blood culture. Despite the institution of antibiotic therapy, the patient suffered from multiple episodes of septic embolism: skin, mucosae, cerebral abscesses, spondylodiscitis and uveitis. He was submitted to heart surgery with miectomy and replacement of the native mitral valve by a mechanical prosthesis, while on antibiotics.info:eu-repo/semantics/publishedVersio

    Cytogenetic characterization of Partamona cupira (Hymenoptera, Apidae) by fluorochromes

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    Four colonies of the stingless bee Partamona cupira (Hymenoptera: Apidae) were cytogenetically analyzed using conventional staining and the fluorochromes CMA3 e DAPI. The females have 2n = 34 chromosomes (2K = 32 M¯+2 A¯). Some females, however, presented an additional large B acrocentric chromosome, to a total of 2n = 35. Chromosome B and the chromosomal pairs 2, 9 and 10 showed CMA 3+ bands, indicating an excess of CG base-pairs. A clear association was verified between the P. helleri B chromosome SCAR marker and the presence of a B chromosome in P. cupira. The data obtained suggests that B chromosomes in P. helleri and P. cupira share a common origin

    Sentimientos de adolescentes con Diabetes Mellitus delante del proceso de vivir con la enfermedad

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    Qualitative research conducted in a diabetes service in the countryside of the state of Ceará, Brazil, with 11 teenagers with diabetes mellitus. The study aimed to understand the experience of adolescents facing the process of living with diabetes. Data were collected in 2007 May and June, through semi-structured interviews. It was observed that the teenager faces difficulties since the moment of diagnosis, especially because their food habits and lifestyles need to change, triggering feelings like fear, insecurity and anger. Over time, they incorporate the necessary changes to treatment and care, and begin to see the disease as normal. One concludes that it is necessary to understand teenagers, their behaviors, fears and desires and support them in the different areas of this experience.Investigación cualitativa, llevada a cabo en un servicio de diabetes del interior del estado de Ceará, Brasil, con 11 adolescentes con diabetes mellitus. El objetivo fue comprender la experiencia del adolescente delante del proceso de vivir con diabetes. Los datos fueron recolectados entre mayo y junio de 2007 a través de entrevistas semi estructuradas. Se observó que el adolescente enfrenta dificultades desde el momento del diagnóstico, sobre todo en el plan alimentar y cambios en el estilo de vida, desencadenando sentimientos como miedo, inseguridad e ira. Con el tiempo, incorporan los cambios necesarios al tratamiento y atención, y llegan a ver la enfermedad como algo normal. En conclusión, que es necesario entender los adolescentes, sus comportamientos, miedos y deseos, y apoyarlos en las diferentes áreas de esta experiencia.Pesquisa de natureza qualitativa, realizada em um serviço de diabetes do interior do Ceará com 11 adolescentes portadores de diabetes mellitus. O estudo objetivou compreender a experiência do adolescente frente ao processo de viver com o diabetes. Os dados foram coletados nos meses de maio e junho de 2007 por meio de entrevista semiestruturada. Constatou-se que o adolescente enfrenta dificuldades desde o momento do diagnóstico, principalmente no plano alimentar e nas mudanças no estilo de vida, desencadeando sentimentos como medo, insegurança e revolta. Com o passar do tempo, incorporam as mudanças necessárias ao tratamento e cuidados; e passam a ver a doença de forma normal. Conclui-se que é necessário compreender os adolescentes, seus comportamentos, medos e anseios e apoiá-los nos diversos âmbitos dessa experiência.Secretaria Municipal de Saúde de Pio IX-PI Programa de Saúde da FamíliaUniversidade Federal do Ceará Faculdade de Farmácia Odontologia e Enfermagem Departamento de EnfermagemUniversidade Federal de São Paulo (UNIFESP) Programa de Pós-Graduação em Saúde ColetivaUNIFESP, Programa de Pós-Graduação em Saúde ColetivaSciEL

    The hidden world within plants: ecological and evolutionary considerations for defining functioning of microbial endophytes

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    All plants are inhabited internally by diverse microbial communities comprising bacterial, archaeal, fungal, and protistic taxa. These microorganisms showing endophytic lifestyles play crucial roles in plant development, growth, fitness, and diversification. The increasing awareness of and information on endophytes provide insight into the complexity of the plant microbiome. The nature of plant-endophyte interactions ranges from mutualism to pathogenicity. This depends on a set of abiotic and biotic factors, including the genotypes of plants and microbes, environmental conditions, and the dynamic network of interactions within the plant biome. In this review, we address the concept of endophytism, considering the latest insights into evolution, plant ecosystem functioning, and multipartite interactions.EU Cost Action [FA1103, 312117]; FWF (Austrian Science Foundation) [P26203-B22, P24569-B25]; Portuguese FCT (Foundation for Science and Technology) [SFRH/BPD/78931/2011]info:eu-repo/semantics/publishedVersio
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